New international research has found that children who are the youngest in their class at school are more likely to be diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) than their older classmates.
Led by Curtin University, Australia, along with UK, French, and US researchers, the new study set out to systematically review previous research which had investigated the relationship between a child’s age in their classroom and their chances of being diagnosed with, or medicated for, ADHD.
The researchers looked at 17 studies across the world which included more than 14 million children from the USA, Spain, Canada, Finland, Germany, the Netherlands, Iceland, Israel, Norway, Sweden, Taiwan and Australia.
The findings, published in the Journal of Child Psychology and Psychiatry, showed that it was more common for the youngest children in a classroom to be diagnosed with ADHD and medicated.
The team added that this appeared be the norm around the world, even in countries with relatively low prescribing rates.
“Our research shows that the ADHD late-birthday effect occurs in both high prescribing countries, like the USA, Canada and Iceland, and in countries where ADHD is far less common, like Finland, Sweden and Taiwan. Our findings challenge the notion that misdiagnosis only happens in countries where there is a high rate of prescriptions for ADHD,” commented lead author Dr. Martin Whitely.
Despite being one of the most commonly diagnosed and medicated childhood psychiatric disorders in the world, ADHD remains difficult to diagnose, as there are no biological markers or physical tests for the condition, with diagnosis based in part on teacher reports of a child’s behaviour.
“It appears that across the globe some teachers are mistaking the immaturity of the youngest children in their class for ADHD. Although teachers don’t diagnose it, they are often the first to suggest a child may have ADHD,” said Dr. Whitely.
Study co-author Professor Jon Jureidini also added that the new review highlights the importance of not only teachers but also doctors and parents being aware of how a child’s relative age in the classroom may impact their behaviour, and that they may need more time to mature.
“Mistaking perfectly normal age-related immaturity for ADHD is just one of many problems with the label. Children who are sleep deprived, bullied, have suffered abuse or have a host of other problems, often get labelled ADHD,” Professor Jureidini said.
“Not only does this result in them getting potentially harmful drugs they don’t need, but their real problems don’t get identified and addressed.”